Abstract/Summary Core B: Flow Cytometry & Cell Sorting Core. The initiation and progression of events leading to type 1 and type 2 diabetes is accompanied by alterations in multiple cell types within the subject. Characterization, tracking and isolation of those cell populations by DRC investigators are enabled by the instruments and expertise available in the Flow Cytometry & Cell Sorting Core. Purpose: The Flow Cytometry & Cell Sorting Core assists investigators whose research requires the characterization of molecular markers in dispersed cells and/or the isolation of cells based on those markers. The Core provides the following services that is currently averaging 5501 accesses and 9419 cytometry/sorting hours by 143 researchers in 20 DRC laboratories: 1. Flow Cytometry. Five high-speed, multi-laser flow cytometers and analysis programs with highly complementary capabilities are available to meet DRC demand for cell characterization. 2. Cell Sorting. Six high-speed, multi-laser fluorescence activated cell sorters enable DRC investigators to isolate cell populations that can then be extensively characterized molecularly or that may be re-introduced to host animals to examine the effect of those cells on disease progression. 3. Information and Training. The Core trains investigators on the proper use of equipment and provides advice on the application of the technology. Benefits to DRC Community: The Core accelerates diabetes research by providing DRC investigators with access to advanced technologies and operational expertise that are beyond the abilities of individual laboratories to maintain. 39 NIH-funded and 31 other diabetes-related projects totaling $13,640,397 annual direct costs have benefited from the practical and economic access to this highly needed technology. Technology Development: Few laboratories have the resources to develop the most advanced capabilities to realize the full potential of the instruments. Support from the DRC enables one Core staff member to spend up to one day a week developing advanced capabilities that the DRC Executive Committee finds to be required by large numbers of DRC investigators. For example, new spectral analysis capabilities on advanced instruments not yet publicly available are now being developed in the Core to increase the accuracy and number of channels available for the analysis of specific cellular populations during disease progression. In the past three years, this Core has been successfully consolidated with other UCSF cytometry and cell sorting facilities to coordinate equipment procurement, expand instrument access and enhance staff availability. A robust co-pay mechanism ensures that DRC support is channeled to diabetes research in an institution-wide Core that provides access to a much greater degree of complementary instrumentation at lowered costs through the defraying of Core maintenance and personnel costs over a larger user base..